Current development of liquid-repellent surfaces is inspired by the self-cleaning abilities of many natural surfaces on animals, insects, and plants. Water droplets on these natural surfaces roll off or slide off easily, carrying the dirt or insects away with them. The presence of the micro/nanostructures on many of these natural surfaces has been attributed to the water-repellency function. These observations have led to enormous interests in manufacturing biomimetic water-repellent surfaces in the past decade, owing to their broad spectrum of potential applications, ranging from water-repellent fabrics to friction-reduction surfaces.
Surfaces having high slip properties and demonstrating anti-adhesive and anti-fouling properties are known. Slippery Liquid-Infused Porous Surfaces (SLIPS) article includes a solid surface having surface features that provide a surface roughness. The roughened surface, which is appropriately chemically or physically modified/conditioned when needed, to provide surface properties compatible with the applied lubricant (referred to herein as “roughened surface”), is coated with a wetting liquid that has a high affinity to conditioned surface, wets the roughened surface, filling the hills, valleys, and/or pores of the roughened surface, overcoats the roughened surface forming an ultra-smooth surface over the roughened surface. Due to the formation of the smooth liquid interface resulting from wetting the roughened surface with the wetting liquid, various liquids, solids and gases have low adherence to the surface, thus reducing drag, fouling, adsorption and improving hydro- and aerodynamic properties of the material. SLIPS surfaces are discussed in International Patent Application Nos. PCT/US2012/21928 and PCT/US2012/21929, both filed Jan. 19, 2012, the contents of which are hereby incorporated by reference in their entireties.
Many surfaces that can benefit from high slip, and anti-adhesive and/or anti-fouling properties are not amenable to surface treatment such as surface roughening treatments used in preparing SLIPS surfaces.